Improvement in furnaces for chloridizing ores



M. PHELPS Furnaces for Chloridizingflre's. 136,261.

Fag JJ.

AM PHpra-uTnosnAPmc on M (oseanws's M00585) 7 U NTTnn STATES PATENT QFTPIQE- IRA M. PHELPS, OF CHICAGO, ILLINOIS.

IMPROVEMENT IN FURNACES EOR CHLORIDIZING ORE S.

Specification forming part of Letters Patent No. 136,261, dated February 25, 187:1.

To all whom it may concern:

Be it known that I, IRA M. PHELPS, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Chloridizing-Furnaces; and I do hereby declare the following to be a full, clear, and exact description thereof which will enable others skilled in the art to which my invention appertains to make and use the same, reference being had to the accompanyin g drawing forming part of this specification, in which- Figure 1 is an end elevation of a chloridizing -furnace embodying my improvements. Fig. 2 is a like elevation with a portion of the outer wall removed, showing the connection of the chlorodizing-pipes. Fig. 3 is a crosssection or plan of the same taken on line a a drawn across Fig. 1; and Fig. 4 is a like section or plan taken on line mm drawn across Fig. 2.

Similar letters of reference indicate like parts in the several figures of the drawing.

The object of my invention is to provide a furnace, so arranged as to so chloridize sulphureted silver-bearing ores as to prevent the escape of the disengaged chlorine and 001m pel its union with the silver; and also to prevent the silver from escaping by 'olatilization before the chloridizatiou is elfeoted; and to that end consists in a furnace provided with a series of horizontal pipes, communicating one with the other, throughwhich the finely-put verized ore is forced by a current of hot air, said pipes being subjected to a high degree of heat by contact with the fire from the furnace, thereby chloridizing the said ores.

In the drawing, A represents the furnace, which is provided at its lower extremity with a fire-box, B, in the usual manner. 0 is a curved or angular pipe, by which the said furnace is connected to the smokestack (not shown.) D is the heater-pipe, which is secured horizontally within the said furnace, immediately over the fire-box, and is so arranged as to cross the same in a zigzag form, and at right angles with the grate-bars. E is a system of horizontal pipes, also secured within the said furnace, immediately over the said heater-pipe, and crossing the same at right angles and parallel with the grate-bars, and

communicate one with the other through connecting-chambers F, formed within the walls of the furnace, thereby forming one continuous pipe. The said heater-pipe extends through the walls of the furnace, and is bent in the form shown in Fig. 1, and extends upward to the upper surface of the furnace, and is there connected with one end of the pipes E. ,G is a hopper which is secured to the upper surface of the furnace, and communicates with the pipes E, as shown by dotted lines, Fig. 2.

A The operation of my said improved'chloridizing-furnace is as follows: The'ore is pulverized to a fine powder, and is thoroughly mixed with a due proportion of common salt, and which said mixture is then introduced into the hopper G, and passes therefrom into the pipe or pipes E, made of cast-iron or fire-clay,

and are kept at a red heat. A current of hot air is then forced into and through pipe D, (which is also made of cast-iron and kept at a low red heat,) by means of a suitable fan, not shown in drawing, thereby forcing or blowing the said ore and mixture in acontinuous stream through the red-hot chloridizing-pipes E, as indicated by the arrows in Fig. 4 of the drawing, and is discharged therefrom into any suitable cooling receptacle or chamber communieating with said pipes, whereby the sulphurcted silver-bearing ore is chlorodized; the escape of the disengaged chlorine is prevented, and is united with the silver, and the es cape of the silver, by volatilization before the chloridization is'elfected, is prevented.

In furnaces in which the ore is blown through the shaft or fine, whether vertical, inclined, or horizontal, the shaft or flue being also used as the conduit for the flame and hot air, the ore must necessarily be introduced at or near the fire-box, where the heat is the greatest. Argentiferous galena and ores containing a considerable proportion of lead cannot be thus treated, as the lead would melt at once, and defeat the object sought. Such ores must be heated more gradually, in order to allow suffi cient time for the lead to become oxidizedi 0., converted into lithargeafter which the temperature may be increased to any degree necessary, without detrimentor damage. Other varieties of argentiferous and most auriferous ores can be submitted at once to the greatest heat of a chloridizing-furnace; and, in the opinion of many metallurgists, with positive advantage.

In the furnace as above described, unlike any other furnace, the ore may be introduced at the upper and coolest portion of the pipe, and discharged from the bottom, the hottest extremity, or it may be introduced at the bottom and discharged at the top. The former method is best adapted to the galenic, while the latter may be more efficient in treating the more refractory, ones.

By the construction and operation of my said furnace, the chlorine gas is kept confined in the pipe in which it is generated, in connection with the heated ore, and under strong atmospheric pressure, thereby securing its union with the precious metals with but little waste thereof, and much less than in furnaces now in use for similar purposes. The loss of volatilized silver is prevented by being converted into heavy chloride before escaping into the cooling-chamber.

The ore is reduced Having thus described the nature and object of my inventioin'what I claim as new, and desire to secure by Letters Patent, is-

1. The process of ehloridizing sulphureted silver-bearin g ores, so as to prevent the escape of the disengaged chlorine and uniting it with the silver, and at the same time preventing the escape of the silver by volatilization before the chloridization is effected, by forcing said ores through a heated pipe or pipes with out bringing said ores in contact with the flame from the furnace, substantially as specified.

2. In the process of chloridizin g snlphureted silver-bearing ores, the use of the horizontal heater-pipe D, and horizontal chloridizing pipes E, substantially as and for the purpose specified.

3. In a ohloridizing-furnace, the combination and arrangement of the horizontal heater pipe 1), horizontal chloridizing pipes E, and chambers F, substantially as and for the purpose specified.

at. Ohloridizing snlphureted silver-bearing ores within heated pipes, in connection with a hot-blast, substantially as specified.

' Iii-A M. PHELPS.

' Witnesses:

N. (J. GRIDLEY, N. H. SHERBUR-NE. 

